rt ， 为啥题解同种做法不卡啊

#include<cstdio>
#include<algorithm>
#define Mod (20170408)
using namespace std;

const int MAXN = 101, MAXM = 20000007;

int n, m, P;

class Matrix {
	private : 
	int a[MAXN][MAXN];
	public : 
	int n, m;
	inline int& operator () (const int &x, const int &y) {
		return a[x][y];
	}
	inline void Init(int x, int y) {
		n = x, m = y;
		for (int i = 1; i <= n; ++ i)
			for (int j = 1; j <= m; ++ j)
				a[i][j] = 0;
	}
	inline void Unit() {
		for (int i = 1; i <= n; ++ i)
			a[i][i] = 1;
	}
	inline Matrix operator * (Matrix &B) {
		Matrix C; C.Init(n, m); 
		for (int i = 1; i <= n; ++ i)
			for (int k = 1; k <= m; ++ k)
				for (int j = 1; j <= B.m; ++ j)
					C(i, j) = (C(i, j) + 1ll * a[i][k] * B(k, j) % Mod) % Mod;
		return C;
	}
}A, B;
inline Matrix fsp(Matrix x, int p) {
	Matrix res; res.Init(P, P); res.Unit();
	for (; p; p >>= 1) {
		if (p & 1) res = res * x;
		x = x * x;
	} 
	return res;
}

int ct, prim[MAXM];
int vis[MAXM];
int cnt[2][MAXN];
inline void Euler() {
	cnt[0][1] = cnt[1][1] = 1;
	for (int i = 2; i <= m; ++ i) {
		++ cnt[0][i % P];
		if (!vis[i]) prim[++ ct] = i;
		else ++ cnt[1][i % P];
		for (int j = 1; j <= ct; ++ j) {
			vis[i * prim[j]] = 1;
			if (i % prim[j] == 0) break;
		}
	}
}
inline void Prew() {
	A.Init(P, P); B.Init(P, P);
	for (int j = 1; j <= P; ++ j) 
		for (int t = 0, i = j; t < P; ++ t, i = i % P + 1)
			A(i, j) = cnt[0][t], B(i, j) = cnt[1][t];
}

int main()
{
	scanf ("%d%d%d", &n, &m, &P);
	Euler(); Prew();
	A = fsp(A, n); B = fsp(B, n);
	return printf ("%d\n", (A(1, 1) - B(1, 1) + Mod) % Mod), 0;
}